Seasonal patterns in the activity and species richness of surface-foraging termites (Isoptera) at paper baits in a tropical Australian savanna

Abstract

The species present, and the frequencies and intensities of termite attack on 600 paper baits exposed at the soil surface were compared over three seasonal exposures and between two savanna sites of contrasting vegetation structure in northern Australia. Eleven species were recorded, with Microcerotermes nervosus and Schedorhinotermes actuosus comprising 43% and 27% of collections respectively. The most commonly sampled species nest underground or build epigeal mounds and are known to feed on sound and decaying wood. Changes in species dominance occurred between seasons and the two forest types. In both vegetation types, the number of species active and the frequency of attack increased with the duration of bait exposure and decreased in the order: transitional > wet > dry. Bait consumption was greater in the site with higher canopy cover, and did not differ significantly between seasons. No direct relationships were noted between rainfall recorded at the sites and species richness, frequency and intensity of attack on baits. We recommend exposure of paper baits for at least 2 mo during the transitional period as the optimal protocol for sampling at the time of greatest activity and diversity of those species within the guild of wood-feeding species regularly attracted to paper baits.

Comparison of Coptotermes formosanus and Coptotermes gestroi (Blattodea: Rhinotermitidae) Field Sites and Seasonal Foraging Activity in Hawaii

“…Buxton (1981) also noted that the number of termites in the colony, the production of new individuals and the amount of food already stored in the nest fluctuated according to the season. In contrast, however, Dawes-Gromadzki & Spain (2003) found no direct relationships between rainfall and termite species richness, or frequency and intensity of attack on baits during a field investigation of seasonal patterns in the activity and species richness of surface-foraging termites at paper baits in a tropical Australian savanna.…”

Seasonal activity patterns of African savanna termites vary across a rainfall gradient

“…While some studies record higher levels of termite abundance and activity during the wettest months of the year in savannas (Buxton, 1981;Pinheiro et al, 2002), others measured higher levels of termite activity in drought years and months of lower rainfall (Ohiagu, 1979;Braack, 1995) while still others recorded highest activity in the transitional season between wet and dry months (Dawes-Gromadzki and Spain, 2003, see also Abensperg-Traun 1991 for similar findings in Western Australia). Such contrasting responses in different savanna areas have resulted in unclear patterns with a need for more comprehensive studies.…”

“…Half (20) of the baits were placed directly on the soil surface, any litter present was brushed aside to ensure direct contact was made with the soil and the base of the bait. These baits were wrapped around the middle with packaging tape to prevent unravelling and secured to the soil surface using a metal tent peg placed through the centre hole of each bait.…”

Interactive Effects of Fire, Rainfall, and Litter Quality on Decomposition in Savannas: Frequent Fire Leads to Contrasting Effects

“…In addition, faunal decomposers, such as earthworms and termites, are sensitive to moisture and temperature levels (Smith and Rust 1994;Curry 1998), becoming less active in cold and dry environments. They are consequently more active during the wet season (Garnsey 1994;Dawes-Gromadzki and Spain 2003;Davies 2010). Warmer and wetter areas (as well as the wet season) are therefore more conducive to high decomposer diversity and activity, potentially contributing to faster rates of decomposition in such areas and seasons.…”